AE environment variables and register_ae

The behavior of the AE process is controlled by these variables, which include executable path, command-line arguments, logging options, paths, and so on. To see which variables are set by an invocation of register_ae, use the --echo option.

--echo

Displays how the compile template is expanded. See the nzsql show output in the --environment description for an example of --echo results.

--environment <variable>

Sets an AE system or user-specific environment variable. You can override the environment variables set by register_ae, use advanced AE registration variables that are not supported by register_ae, and set user-specific environment variables.

Note: The starting substring “NZAE” is reserved for AE system environment variables and should not be used for user-specific variables.

User-specific variable example:

--environment "'APPLY_INFO'='true'"

The full power of AEs is available through the AE system environment variables. For more information, see Introducing AE environment variables.

When a function is registered, you can display the effects of the –environment options (and many other NPS system SQL function settings) by using the SQL show command. A table function that calls a Java AE is registered in the following example:

register_ae
--language java
--template udtf
--version 3
--sig "applyOperationV2Tf(varargs)"
--return "table(result double)"
--define java_class=org.netezza.education.ApplyDriverV2 --
level 1
--environment "'APPLY_FUNCTION'='OPERATION'"

Running show in nzsql produces the following example:

SHOW FUNCTION applyOperationV2Tf;
RESULT | FUNCTION | BUILTIN | ARGUMENTS
--------------------------------+--------------------+---------+---
TABLE(RESULT DOUBLE PRECISION) | APPLYOPERATIONV2TF | f | ()

Use the verbose option to display additional information. In addition to using the show command, you can run register_ae with the --echo option to display this output. To fully understand the output, see Introducing AE Environment Variables. Below are the AE environment variables from the applyOperationV2Tf example:

SHOW FUNCTION applyoperationV2TF VERBOSE;
APPLY_FUNCTION=OPERATION
NZAE_REGISTER_NZAE_DYNAMIC_ENVIRONMENT=0
NZAE_REGISTER_NZAE_EXECUTABLE_PATH=
/nz/export/ae/languages/java/6.13.0/jdk1.6.0_13/bin/java
NZAE_REGISTER_NZAE_HOST_ONLY_NZAE_DEBUG=1
NZAE_REGISTER_NZAE_HOST_ONLY_NZAE_PREPEND_LD_LIBRARY_PATH=
/nz/export/ae/adapters/java/3/sys/nz/lib/host
NZAE_REGISTER_NZAE_HOST_ONLY_NZAE_REMOTE =0
NZAE_REGISTER_NZAE_HOST_ONLY_NZAE_REMOTE_LAUNCH_VERBOSE=0
NZAE_REGISTER_NZAE_HOST_ONLY_NZAE_REMOTE_NAME=
NZAE_REGISTER_NZAE_HOST_ONLY_NZAE_REMOTE_NAME_DATA_SLICE=0
NZAE_REGISTER_NZAE_HOST_ONLY_NZAE_REMOTE_NAME_SESSION=0
NZAE_REGISTER_NZAE_HOST_ONLY_NZAE_REMOTE_NAME_TRANSACTION=0
NZAE_REGISTER_NZAE_LOG_IDENTIFIER=applyOperationV2Tf(varargs)
NZAE_REGISTER_NZAE_NUMBER_PARAMETERS=1
NZAE_REGISTER_NZAE_PARAMETER1=org.netezza.education.ApplyDriverV2
NZAE_REGISTER_NZAE_PREPEND_CLASSPATH=
/nz/export/ae/applications/dev/admin/java/:
/nz/export/ae/applications/dev/admin/java:
/nz/export/ae/adapters/java/3/sys/nz/java/nzae.jar
NZAE_REGISTER_NZAE_PREPEND_PATH=
/nz/export/ae/languages/java/6.13.0/jdk1.6.0_13/bin
NZAE_REGISTER_NZAE_SPU_ONLY_NZAE_DEBUG=1
NZAE_REGISTER_NZAE_SPU_ONLY_NZAE_PREPEND_LD_LIBRARY_PATH=
/nz/export/ae/adapters/java/3/sys/nz/lib/spu10
NZAE_REGISTER_NZAE_SPU_ONLY_NZAE_REMOTE =0
NZAE_REGISTER_NZAE_SPU_ONLY_NZAE_REMOTE_LAUNCH_VERBOSE=0
NZAE_REGISTER_NZAE_SPU_ONLY_NZAE_REMOTE_NAME=
NZAE_REGISTER_NZAE_SPU_ONLY_NZAE_REMOTE_NAME_DATA_SLICE=0
NZAE_REGISTER_NZAE_SPU_ONLY_NZAE_REMOTE_NAME_SESSION=0
NZAE_REGISTER_NZAE_SPU_ONLY_NZAE_REMOTE_NAME_TRANSACTION=0

The prefix NZAE_REGISTER is reserved for internal use by register_ae. At runtime this prefix is removed. For example, NZAE_REGISTER_NZAE_NUMBER_PARAMETERS=1 becomes NZAE_NUMBER_PARAMETERS=1.

If in this case NZAE_NUMBER_PARAMETERS was previously defined, the NZAE_REGISTER version is discarded. Thus, an AE environment variable that starts with NZAE_REGISTER can be overridden by using the register_ae --environment option. As an example, the Java registration above is changed to add a property and a command-line argument to the main Java class:

register_ae
--language java
--template udtf
--version 3 --db dev
--sig "applyOperationV2Tf(varargs)"
--return "table(result double)"
--define java_class=org.netezza.education.ApplyDriverV2 --
level 1
--environment "'APPLY_FUNCTION'='OPERATION'"
--environment "'NZAE_NUMBER_PARAMETERS'='3'"
--environment "'NZAE_PARAMETER1'='-Dmyprop=x'"
--environment "'NZAE_PARAMETER2'='org.netezza.education.ApplyDriverV2'"
--environment "'NZAE_PARAMETER3'='my parameter'"

Note: The --environment option overrides are not prefixed with NZAE_REGISTER.

You can use the register_ae ability to transform options to system AE environment variables and NPS system function settings when using AE in advanced methods and for diagnosing problems.